For store separation analysis the availability of reliable aerodynamic interference data is of prime importance. Presently a number of sources is used to obtain these data, such as wind tunnel measurements, panel method calculations and calculations based on measured store separation trajectories. To gain more insight into the limitations of the various sources as well as to obtain a tool which can be used for the certification of new stores for existing aircraft an aerodynamic load measuring store was developed. It consists of a support structure to be mounted from 14 or 30 inch bomb racks, a load measuring balance, and a shape representing the store to be analyzed. The shape is replaceable. A flight test program has been carried out in August 1977 with a store resembling a BLU 1/B, on an NF-5A aircraft in various configurations. The results are compared with wind tunnel data from various sources, panel method calculation results and data obtained from in-flight separation tests. It is shown that in-flight measurement of aerodynamic loads will allow a reduction in the number of flight tests required to demonstrate safe separation.